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Published 1980

Scram is a game designed by Chris Crawford for the Atari 800 and released by Atari. Written in Atari BASIC, Scram utilized differential equations to simulate reactor behavior. In the game, the player controlled the valves and switches of a nuclear reactor directly with the joystick. Occasionally, earthquakes would occur and the player would analyze the heat readings and dispatch repair crews to the affected area of the plant.

The game display showed a schematic-like representation of a light water reactor, typical of nuclear reactors in use in the United States at that time. The reactor core was on the left of the screen, with the primary coolant loop to its immediate right. Further right was the secondary cooling loop, and finally the tertiary cooling loop and its associated cooling tower.

The user interacted with the game by moving the joystick, which made a cursor jump from one "hot spot" to another on the screen, each one controlling one part of the reactor systems. There were hot spots for the control rods, cooling pumps and valves. The user could experiment with the reactor systems by moving the joystick up and down, operating the equipment. It was possible to simulate a meltdown by shutting off the primary cooling pumps and withdrawing the control rods all the way.

The game had several skill levels, which controlled the frequency of earthquakes and the "obviousness" of the damage. In the event of an earthquake the screen would shake and a breaking sound would be heard if there was damage. The user then had to watch the on-screen displays to try to isolate where the problem was.

From Softline Magazine, Issue #2:

Atari (Sunnyvale, CA).

Scram presents a simulation of a nuclear power facility, modeled after the Three Mile Island Nuclear Power Plant Unit 2. The various mechanisms of the plant appear in brilliant blues, reds, greens, and yellows. As you might imagine, the game is considerably more difficult to play in black and white than in color; the valve settings and water circulation levels are harder to see.

After studying the Environmental Impact Report and Final Safety Analysis Report, the Nuclear Regulatory Commission steps in to issue a safety license to the plant. Players with a vehement dislike for government red tape will get a vicarious thrill here; the entire licensing procedure takes only five seconds, hardly leaving protestors time to paint their signs.

The major components of the pressurized water reactor are the reactor core, generator, hyperbolic cooling tower, and three circulating water loops. These are interconnected by a series of pumps and valves. Temperatures at seven major sites are displayed, and the net energy of the system (your score) is indicated at the lower right of the screen. Left to its own devices, the station, as in reality, will produce megawatt hours of energy at a uniform rate. This would not make for a particularly interesting or eventful game, so Nature steps in to liven things up a bit, providing earthquakes in the form of loud rumbling noises from the audio and tremors in the visual display. Every quake breaks one pump or valve which must be repaired before disaster strikes . . . or rather, melts down. Determining which valve or pump needs repair calls for careful attention to the temperature gauges and testing of all systems to be sure each performs its specified function.

A work force of eighty men stands ready to help. After a break has been located, five men are sent to repair it. Having suffered their maximum allowable exposure to radiation, these men will never return. In locating the trouble spot, you're allowed a total of sixteen guesses, right or wrong; a wrong guess uses men just as irreversibly. After these have been used up, there is no way to repair a break. The object of Scram is to produce as much net energy as possible while repairing all breaks. A successful end to the game is achieved with a cold shutdown, accomplished by dropping the control rods into the reactor core. Be forewarned, however; it takes approximately five minutes to reduce the reactor temperature from 655 degrees to 200, and earthquakes are not obliging enough to allow an uneventful shutdown.

Scram has nine risk/skill levels, with the higher levels experiencing more frequent earthquakes. Producing five hundred megawatt hours of energy at level nine qualifies the player as a senior reactor operator. Most players will make rapid progress through the first several risk levels. A bar that appears above or below each temperature reading indicates rises or drops in temperature and serves as a handy visual aid. When speed is important, the bars appear much faster than degree changes. There are also two very important pumps which, when inactive, rapidly produce a condition known as steam voiding (very serious), and from there, a quick meltdown. It would obviously he quite helpful to the novice to know the locations of these two pumps ahead of time . . . but why interfere with the thrill of discovery?

The Scram instruction manual is needlessly wordy and confusing. The author (whom Atari keeps anonymous) has an annoying habit of using too many abbreviations in too short a time. Only a reader with perfect retention will be able to avoid flipping back and forth, while struggling to recall the meanings of PWR, RCS, HPI, and LOCA. Understanding is desirable, hut such a level of comprehension is not essential to a successful run at the game. Since the game itself is a series of cause/effect steps, it's not necessary to remember what a valve is called to know when it needs to be closed.

Scram will run on either the Atari 400 or 800 computer.
Tape only. $19.95.

Identifier a8b_SCRAM_1980_Atari_US_req_OSb_BASIC
Emulator a800xl
Emulator_ext atr
Mediatype software
Scanner Internet Archive Python library 0.6.5
Publicdate 2014-06-15 02:30:33
Addeddate 2014-06-15 02:30:33
Creator Chris Crawford
Date 1980
Year 1980
Language English


Floppy Directory:

DOS.SYS (039 sectors)
DUP.SYS (042 sectors)
SCRAM.BAS (104 sectors)
SCRAM.BAK (104 sectors)
AUTORUN.SYS (002 sectors)


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Uploaded by
Jason Scott
on 6/15/2014